Bigeye thresher vs Fatspine spurdog

Alopias pelagicus compared with Squalus crassispinus

Key Differences

• Bigeye thresher is Endangered while Fatspine spurdog is Least Concern.

Taxonomic Classification

Rank	Bigeye thresher	Fatspine spurdog
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Chondrichthyes (Cartilaginous Fish)	Elasmobranchii
Order	Lamniformes (Mackerel Sharks)	Squaliformes (Squaliformes)
Family	Alopiidae	Squalidae
Genus	Alopias	Squalus
Species	Alopias pelagicus	Squalus crassispinus

Evolutionary Relationship

Bigeye thresher and Fatspine spurdog share a common ancestor at the Phylum level: Chordata. (Chordates)

Conservation Status

Bigeye thresher

EN — Endangered

Fatspine spurdog

LC — Least Concern

Physical Characteristics

Attribute	Bigeye thresher	Fatspine spurdog
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Bigeye thresher

Habitat

Typically found in marine environments from coastal waters to deep ocean.

Range

Distributed across Colombia and Taiwan. Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Fatspine spurdog

Bigeye thresher

The Bigeye thresher (Alopias pelagicus) is a species in the genus Alopias. It is currently classified as Endangered on the IUCN Red List. Typically found in marine environments from coastal waters to deep ocean.